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Power operated relief valves for boiler or superheater headers

Solid rendition of MOGAS PORV valve

ASME 1500 / 2500 / 4500 Class: Prevents Excessive Pressure Build-up

The MOGAS PORV, a pneumatic actuated pressure relieving valve, prevents excessive system pressure accumulation. The set pressure of the PORV is lower than that of the spring-loaded safety valve to prevent or reduce the number of lifts of the safety valve, thus extending their life. The PORV is available either non-stamped or with the “V” stamp. The “V” stamped PORV has been flow certified by the National Board of Boiler and Pressure Vessel Inspectors.

The PORV operates as a system. The MOGAS ball valve is normally closed. The pressure switch senses steam pressure and closes an electrical switch when the pressure exceeds a predetermined point. This, in turn, energizes the solenoid valve, which pressurizes the “to open” cylinder port of the pneumatic actuator, opening the ball valve. When the pressure switch senses that the steam pressure has returned to normal, the electrical switch within the pressure switch opens, de-energizing the solenoid valve and closes the MOGAS ball valve.

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  • ASME “V” stamp available
  • Live loading ensures zero emissions from stem packing in the most severe temperature shocks
  • High nickel alloy base ball and seat with a proprietary coating ensures superior wear resistance
  • Quick operating pneumatic actuator decreases wear on sealing surfaces
  • Field repairable
Power Generation Industry

Overpressure relief of boiler/superheater header


2-1/2 to 4 inch

Standard Components
  • MOGAS ball valve
  • Actuator
  • Four-way electrically operated solenoid valve
  • Control box
  • Limit switch
Optional Components
  • Pressure switch
  • Siphon tube
  • Air reservoir kit
End Connections

Per customer specification